Summarize constructor initializers.

pkg/analyzer/lib/src/summary/summarize_const_expr.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library serialization.summarize_const_expr;
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/scanner.dart';
 import 'package:analyzer/src/summary/format.dart';
 import 'package:analyzer/src/summary/idl.dart';
 
 /**
+ * Serialize the given constructor initializer [node].
+ */
+UnlinkedConstructorInitializer serializeConstructorInitializer(
+    ConstructorInitializer node,
+    UnlinkedConstBuilder serializeConstExpr(Expression expr)) {
+  if (node is ConstructorFieldInitializer) {
+    return new UnlinkedConstructorInitializerBuilder(
+        kind: UnlinkedConstructorInitializerKind.field,
+        name: node.fieldName.name,
+        expression: serializeConstExpr(node.expression));
+  }
+  if (node is RedirectingConstructorInvocation) {
+    return new UnlinkedConstructorInitializerBuilder(
+        kind: UnlinkedConstructorInitializerKind.thisInvocation,
+        name: node?.constructorName?.name,
+        arguments:
+            node.argumentList.arguments.map(serializeConstExpr).toList());
+  }
+  if (node is SuperConstructorInvocation) {
+    return new UnlinkedConstructorInitializerBuilder(
+        kind: UnlinkedConstructorInitializerKind.superInvocation,
+        name: node?.constructorName?.name,
+        arguments:
+            node.argumentList.arguments.map(serializeConstExpr).toList());
+  }
+  throw new StateError('Unexpected initializer type ${node.runtimeType}');
+}
+
+/**
  * Instances of this class keep track of intermediate state during
  * serialization of a single constant [Expression].
  */
 abstract class AbstractConstExprSerializer {
   /**
    * See [UnlinkedConstBuilder.operations].
    */
   final List<UnlinkedConstOperation> operations = <UnlinkedConstOperation>[];
 
   /**
@@ skipping 10 matching lines @@
    * See [UnlinkedConstBuilder.strings].
    */
   final List<String> strings = <String>[];
 
   /**
    * See [UnlinkedConstBuilder.references].
    */
   final List<EntityRefBuilder> references = <EntityRefBuilder>[];
 
   /**
+   * Return `true` if a constructor initializer expression is being serialized
+   * and the given [name] is a constructor parameter reference.
+   */
+  bool isConstructorParameterName(String name);
+
+  /**
    * Serialize the given [expr] expression into this serializer state.
    */
   void serialize(Expression expr) {
     if (expr is IntegerLiteral) {
       _pushInt(expr.value);
     } else if (expr is DoubleLiteral) {
       operations.add(UnlinkedConstOperation.pushDouble);
       doubles.add(expr.value);
     } else if (expr is BooleanLiteral) {
       if (expr.value) {
         operations.add(UnlinkedConstOperation.pushTrue);
       } else {
         operations.add(UnlinkedConstOperation.pushFalse);
       }
     } else if (expr is StringLiteral) {
       _serializeString(expr);
     } else if (expr is SymbolLiteral) {
       strings.add(expr.components.map((token) => token.lexeme).join('.'));
       operations.add(UnlinkedConstOperation.makeSymbol);
     } else if (expr is NullLiteral) {
       operations.add(UnlinkedConstOperation.pushNull);
     } else if (expr is Identifier) {
-      references.add(serializeIdentifier(expr));
-      operations.add(UnlinkedConstOperation.pushReference);
+      if (expr is SimpleIdentifier && isConstructorParameterName(expr.name)) {
+        strings.add(expr.name);
+        operations.add(UnlinkedConstOperation.pushConstructorParameter);
+      } else {
+        references.add(serializeIdentifier(expr));
+        operations.add(UnlinkedConstOperation.pushReference);
+      }
     } else if (expr is InstanceCreationExpression) {
       _serializeInstanceCreation(expr);
     } else if (expr is ListLiteral) {
       _serializeListLiteral(expr);
     } else if (expr is MapLiteral) {
       _serializeMapLiteral(expr);
     } else if (expr is MethodInvocation) {
       String name = expr.methodName.name;
-      if (name != 'identical') {
-        throw new _ConstExprSerializationError(
-            'Only "identity" function invocation is allowed.');
-      }
-      if (expr.argumentList == null ||
-          expr.argumentList.arguments.length != 2) {
-        throw new _ConstExprSerializationError(
-            'The function "identity" requires exactly 2 arguments.');
-      }
+//      if (name != 'identical') {

[Paul Berry, 2016/02/08 14:53:12]

Can you include a comment explaining why this code is commented out?

[scheglov, 2016/02/08 16:29:51]

It should not be commented out.
I will uncomment it.

+//        throw new _ConstExprSerializationError(
+//            'Only "identity" function invocation is allowed.');
+//      }
+//      if (expr.argumentList == null ||
+//          expr.argumentList.arguments.length != 2) {
+//        throw new _ConstExprSerializationError(
+//            'The function "identity" requires exactly 2 arguments.');
+//      }
       expr.argumentList.arguments.forEach(serialize);
       operations.add(UnlinkedConstOperation.identical);
     } else if (expr is BinaryExpression) {
       _serializeBinaryExpression(expr);
     } else if (expr is ConditionalExpression) {
       serialize(expr.condition);
       serialize(expr.thenExpression);
       serialize(expr.elseExpression);
       operations.add(UnlinkedConstOperation.conditional);
     } else if (expr is PrefixExpression) {
@@ skipping 213 matching lines @@
  * Error that describes a problem during a constant expression serialization.
  */
 class _ConstExprSerializationError {
   final String message;
 
   _ConstExprSerializationError(this.message);
 
   @override
   String toString() => message;
 }